Ballast forms the trackbed of a railway, used to bear the load from the railway ties to hold the track in place as the trains roll by. It is usually made of crushed stone at least 150 mm in thickness, these stones being irregularly cut so that they can properly interlock and grip the ties in order to fully secure them against movement. (Spherical stones cannot do this.)
One function of ballast (and the root of the word itself) is to provide stability. In mediaeval days, ballast was used to steady a ship to prevent it drifting; Heb 2:1 says, ‘we must pay the most careful attention to what we have heard, so that we do not drift away.’ Ballast prevents drifting.
One of the functions of meeting together as Christians to prevent this drifting, this tendency to deviate from truth and from faith. Peter talks about us being ‘living stones’ which are being built into a spiritual house. (1 Pet 2:5) We are not meant to be loosely scattered stones; we are meant to be closely compacted together. We provide ballast for each other, a reminder that all we have heard about God is true. As we spur each other on to good deeds, as we talk about the things of God together, as we pray and study God’s word together, stability is brought into our lives.
Fellowship is a joy and a delight, but it’s also hard work. Stones of uneven edges and sizes rub against each other. We irritate each other. Our different personalities don’t always mesh well. We can be thoughtless and inconsiderate as well as caring and compassionate. But fellowship is essential if we’re going to grow spiritually, for God is building a spiritual house and these living stones have to be built together,.
There is no place for splendid isolation in the church, no place for lofty haughtiness or spiritual posturing. Our function is ballast: unglamorous, unfashionable crushed stones, knitted together to provide a highway for our King to travel on. It’s only as we live together in unity and harmony that others see God. That’s a new purpose to hold onto in the indignity of being compacted together on the track of life!